In all forms of responses, be it short or long, the selection of quotes is an art. There is no such thing as "evidence I cannot not use" but there is such a thing as "evidence I quoted poorly".
Take the following George Orwell 1984 extract:
In its second minute the Hate rose to a frenzy. People were leaping up and down in their places and shouting at the tops of their voices in an effort to drown the maddening bleating voice that came from the screen. The little sandy-haired woman had turned bright pink, and her mouth was opening and shutting like that of a landed fish. Even O’Brien’s heavy face was flushed. He was sitting very straight in his chair, his powerful chest swelling and quivering as though he were standing up to the assault of a wave. The dark-haired girl behind Winston had begun crying out ‘Swine! Swine! Swine!’ and suddenly she picked up a heavy Newspeak dictionary and flung it at the screen. It struck Goldstein’s nose and bounced off; the voice continued inexorably. In a lucid moment Winston found that he was shouting with the others and kicking his heel violently against the rung of his chair. The horrible thing about the Two Minutes Hate was not that one was obliged to act a part, but, on the contrary, that it was impossible to avoid joining in. Within thirty seconds any pretence was always unnecessary. A hideous ecstasy of fear and vindictiveness, a desire to kill, to torture, to smash faces in with a sledge-hammer, seemed to flow through the whole group of people like an electric current, turning one even against one’s will into a grimacing, screaming lunatic. And yet the rage that one felt was an abstract, undirected emotion which could be switched from one object to another like the flame of a blowlamp.
Imagine you are trying to make a point about how individuals are often subconsciously motivated by groups to behave in the same way.
You want to make a comment on the sentence: The horrible thing about the Two Minutes Hate was not that one was obliged to act a part, but, on the contrary, that it was impossible to avoid joining in.
Here are two different quotes taken from the same sentence.
"[it] was not that one was obliged to act a part, but, on the contrary, that it was impossible to avoid joining in"
Winston's inability to resist against the Two Minute Hate is seen in the quote ""[it] was not that one was obliged to act a part, but, on the contrary, that it was impossible to avoid joining in". High modality is used to show the strength of collective motivation and the helplessness of the individual whose behaviours are influenced by the group.
"impossible to avoid joining in"
The inability of the individual to resist against acting according to collective behaviour is illustrated when Winston found it "impossible to avoid joining in" the Two Minute Hate. The use of high modality creates an imperative tone which portrays the overwhelming influence a collective can have over the one.
Quote number 1's main issue is that it was too long for the technique to apply to the entire thing. There were many other techniques happening in the same space. This makes the analysis very "loose" and detracts from your message. The way the quote was presented was also very jarring and deliberate. This happens when the quote is too long.
Quote number 2 is short, is encompassed entirely by the technique mentioned, and worked into the sentence cohesively. This is more succinct to read and much more goal directed.
Make sure you keep this in mind before finding quotes for your responses!